Thermoplastic polyhydroxyether with polychloroprene and laminates thereof



United States Patent Ofilice 3,3982% Patented Mar. 7, 1967 This invention relates to thermoplastic polyhydroxyether adhesive compositions which bond with great strength at low temperatures. More particularly, the invention relates to laminates of thermoplastic polyhydroxyether compositions which develop at low temperatures bond strengths heretofore achieved only at temperatures several hundred Fahrenheit degrees higher.

As the use of thermoplastic polyhydroxyether as an adhesive has widened to include adhesion to a great variety of substrates it has become apparent that the high bonding temperatures used for maximum strength e.g., 600 to 700 F. subtly atfected certain substrates. For example, aluminum laminae were sometimes annealed during the bonding operation. It was desirable, therefore, to reduce the bonding temperatures, but importantly, without a sacrifice in final bond strength, and if possible without loss of the other numerous advantageous properties of thermoplastic polyhydroxyether.

It has now been discovered that the bonding temperature required to obtain laminates of maximum bond strength with thermoplastic polyhydroxyether can be lowered by 100 to 200 Fahrenheit degrees and more by the presence of a chloroprene polymer in the thermoplastic polyhydroxyether.

It is a significant advantage of the present laminates that substantial improvement in shear and peel strength is obtained without the use of primers being required.

It is another significant advantage of these compositions that they are transparent.

Adhesive compositions have now been found which provide the outstanding bond strengths, creep resistance, and versatility of thermoplastic polyhydroxyether, but which develop maximum bond strength at surprisingly lower temperatures than straight polyhydroxyether, i.e. polyhydroxyether not blended with a chloroprene polymer. The thermoplastic polyhydroxyether compositions of the present invention can be applied to adherends from solution as by spraying, dipping, brush flow coating, impregnation or the like; by melt applying as in extrusion coating, powder coating, flame spraying, and fluid bed coating or the like; and importantly by film laminating.

I It is a significant advantage of the thermoplastic polyhydroxyether compositions herein described as an adhesive bonding material that they are available in the form of a flat sheet or as film on a roll. Some of the advantages gained by use of thermoplastic polyhydroxyether composition films as an adhesive material include:

(1) A single component system, no mixing to form the adhesive (2) Unlimited shelf life (3) N liquids to be handled (4) No volatiles (5) No priming of the adherend necessary (6) No prolonged curing cycles (7) Bonds of great strength obtained (8) Readily controllable glue line thickness (9) Absolute freedom from pinholes (10) Ultra-thin laminates feasible (11) Lower cost because less material required (12) No necessity of supporting web for a film adhesive (13) Thermoplastic films are readily produced by variety of inexpensive means (14) Reproducible bonding effects; no vagaries due to cure cycles and storage.

There has not been known prior to thermoplastic polyhydroxyether a thermoplastic material possessing the above attributes. In fact, there has not been known a widely adhesive thermoplastic film. Now with the compositions of the present invention, the advantageous attributes of thermoplastic polyhydroxyether can be taken advantage of with many more substrates such as paper, wood, heat sensitive steels and aluminum.

The thermoplastic polyhydroxyether adhesive compositions herein described lend themselves to coating virtually any surface having any contour. Moreover, a coating of the thermoplastic polyhydroxyether adhesive compositions is in itself a base material or primer to which other materials can be bonded using the thermoplastic polyhydroxyether composition as the adhesive.

Although thermosetting adhesive films are known their properties and advantages do not begin to compare with those of the thermoplastic polyhydroxyether composition adhesive films described herein. Whereas a thermosetting film requires a chemical reaction to bond, the thermoplastic polyhydroxyether adhesive compositions of this invention require only as much temperature and pressure as is necessary to make the composition flow into intimate contact with the adherend. This can be a matter of a few seconds or only a brief fraction of a second. A summary of advantages of thermoplastic polyhydroxyether composition adhesive films over a typical thermosetting resin film, phenolic nit-rile, is presented in Table I.

TABLE I.OOMPARISON OF STORAGE, HANDLING, AND APPLICATION CONDITIONS FOR BONDING FILMS Class Thermosettiug Thermoplastic. Type ofr Phenolic nitrile Polyhydroxyether. Unsupported film, Unsupported film,

polyethylene liner.

no liner. Volatile content Film exposed for 1 hour at 350 F., less The thermoplastic polyhydroxyether adhesive compositions of the present invention are, as illustrated in Table I, in essentially final chemical form and need only be caused to flow for a moment in order to be activated into bonding to an adherend. Activation is by heating either the substrate and pressing the thermoplastic polyhydroxyether adhesive composition thereagainst or heating the thermoplastic polyhydroxyether adhesive composition in some manner e.g., radiant heating, convection, induction, electrically, ultrasonically, et cetera and pressing the adherend against the polymer or a heated particulate adherend can be blown against the thermoplastic polyhydroxyether adhesive composition. The superiority of thermoplastic polyhydroxyether adhesive compositions over other thermoplastics in terms of bond strength is shown in Table I1 following.

1 ASTM D-1002.

9 Neoprene AC.

In general, what is required to adhere the thermoplastic polyhydroxyether adhesive compositions to an adherend is to flux the composition at the interface of two materials. Fluxing is flow under heat and usually pressure and is most easily accomplished by the input of sufl'icient heat into the area to be bonded. It is to be emphasized that actual flow is not necessary because the polyhydroxyether composition can be activated into bonding without flow as occurs for example in some solution coatings. Generally a short bake at moderate temperatures improves the bond obtained from solution coatings. The use of pressure also assists in obtaining good bonding. Typical of amorphous thermoplastics, polyhydroxyethers have no distinct melting point or a narrow melting range but rather soften over a wide temperature range. At the low end of the softening range heat alone may not be sufficient to flux the resin as it is sufiicient at the high end of the range, but a combination of mild heat and pressure will cause the polyhydroxyether compositions to fiow.

The terms structural element and structural elements as used herein refer to an assembly or assemblies of one or more discrete, planar, curvilinear, rectangular, round, or odd shaped objects and thermoplastic 'polyhydroxyether adhesive composition. The assembly is characterized by an adhesive bond between the thermoplastic polyhydroxyether adhesive composition and the object or objects. The term comprehends, therefore, structural elements comprising an adherend such as a substrate and an adhering layer of thermoplastic polyhydroxyether adhesive composition as in a two-ply laminate or a coated substrate; structural elements comprising an interlayer of thermoplastic polyhydroxyether adhesive composition sandwiched between and adhered to two similar or dissimilar adherends or laminae as in a plural ply laminate; structural elements comprising a thermoplastic polyhydroxyether adhesive composition matrix surrounding and adhered to as a bond and/or a support for variously shaped and sized adherends such as articles of varying porosities, e.g., as the bonding agent and/or substrate in sandpaper and fiber reinforced plastic articles; structural elements comprising structural members bonded together either closely adjacent or spaced apart by the thermoplastic polyhydroxyether adhesive composition elements and combinations of the foregoing. The adhered preferably is readily wettable by the thermoplastic polyhydroxyether adhesive compositions either because of a surface pretreatment or cleanliness and/or because of its nature i.e. a polar nature such as characterizes metals, glass, and Wood and is absent in polyethylene, or for any other reason.

Chloroprene polymers constitute a well known class of oil-resistant synthetic rubbers. Polychloroprcne which is preferred herein can be prepared by the polymerization of chloroprene(2-chloro-1,3-butadiene), copolymers of chloroprene with other copolymerizable monomers, such as styrene, u-methyl styrene, acrylonitrile, hydrocarbon dienes e.g. 1,3-butadiene and the like in minor amounts, especially up to about 20% by weight can also be used herein.

Broad ranges of chloroprene polymer concentration in polyhydroxyether are suitable. In general, from about 3 parts to about 33 parts or higher up to 50 parts per 100 parts of the poiyhydroxyether/chloroprene polymer adhesive composition provides substantial reductions in bonding temperature required for laminates having high shear strength bonds without undue modification of the desirable properties of the polyhydroxyether, including transparency.

Reduced viscosity herein is defined as the specific viscosity (ie, the viscosity of the solution minus the viscosity of the solvent divided by the viscosity of the solvent) divided by the concentration of the solution.

The term thermoplastic polyhydroxyether herein refers to substantially linear polymers having the general formula wherein D is the radical residuum of a dihydric phenol, E is an hydroxyl containing radical residuum of an epoxide, and n represents the degree of polymerization and is at least 30 and is preferably 80 or more. Polyhydroxyethers having a melt fiow of less than 7 decigrams/minute determined as hereinafter described are preferred. The term thermoplastic polyhydroxyether is intended to include mixtures of. at least two thermoplastic polyhydroxyethers.

The dihydric phenol contributing the phenol radical residuum D, can be either a dihydric mononuclear phenol such as hydroquinone and resorcinol or a dihydric polynuclear phenol such as those having the general formula )r (YOFI ArR -A1'OH HO L J wherein Ar is an aromatic divalent hydrocarbon such as naphthylene and, preferably, phenylene, Y and Y which can be the same or different are alkyl radicals, preferably having from 1 to 4 carbon atoms, halogen atoms, i.e, fluorine, chlorine, bromine, and iodine, or alkoxy radi cals, preferably having from 1 to 4 carbon atoms, r and z are integers having a value from 0 to a maximum value corresponding to the number of hydrogen atoms on the aromatic radical (Ar) which can be replaced by substituents and R is a bond between adjacent carbon atoms as in dihydroxydiphenyl or is a divalent radical including, for example C H o O-, -S, -SO-, SO and SS, and divalent hydrogen radicals such as alkylene, alkylidene, cycloaliphatic e.g. cycloalkylene and cycloalkylidene, halogenated, alkoxy or aryloxy substituted alkylene, alkylidone and cycloaliphatic radicals as well as alkarylene and aromatic radicals including halogenated, alkyl, alkoxy or aryloxy substituted aromatic radicals and a ring fused to an Ar group; or R can be polyalkoxy, or polysiloxy or two or more alkylidene radicals separated by an aromatic ring, a tertiary amino group, an ether linlo age, a carbonyl group or a sulfur containing group such as sulfoxide, and the like.

The bis(hydroxyphenyl)alkanes such as 2,2-bis(4-hydroxyphenyl) propane, 2,4 dihydroxydiphenylmethane, bis(2 hydroxyphenyl)methane, bis (4 hydroxyphenyl) methane, bis(4-hydroxy 2,6-dimethyl-S-methexyphenyl) methane, 1,l-bis(4-hydroxy-ahenyl)ethane, 1,2-bis(4-hydroxyphenyDethane, 1,l-bis(4-hydroxy Z-chlorophenyl) ethane, 1,l-bis(3-methyl-4-hydroxyphenyl) ethane, 1,3-bis (3-methyl-4-hydnoxyphenyl propane, 2,2-bis (3-phenyl-4- hydroxyphenyl)propane, 2,2-bis(3-isopropyl 4-hydroxyphenyl)propane, 2,2 bis(Z-isopropyl 4-hydroxyphenyl) propane, 2,2-bis(4-hydroxynaphthyl) propane, 2,2-bis(4- hydroxyphenyl) pentane, 3,3 bis(4 hydroxyphenyl)pentane, 2,2-bis(4-hydroxyphenyl)heptane, bis (4 hydroxyphenyl phenylmethane, bis (4-hydroxypheny1 cyclohexylmethane, 1,2-bis (4 hydroxyphenyl) -l,2-bis(phenyl) propane, 2,2-bis(4-hydroxyphenyl)-1-phenyl-propane and the like;

Di(hydroxyphenyl)sulfones such as bis(4-hydroxyphenyl)sulfone, 2,4'-dihydroxydiphenyl sulfone, 5-chloro- 2,4'-dihydroxydiphenyl sulfone, 5-chloro-4,4'-dihydroxydiphenyl sulfone, and the like;

Di(hydroxyphenyl)ethers such as bis(4-hydroxyphenyl)- ether, the 4,3-, 4,2'-, 2,2, 2,3-, dihydroxydiphenyl ethers, 4,4'-di-hydroxy-2,o-dimethyldiphenyl ether, bis(4-hydroxy- 3-isobutylphenyl) ether, bis(4-hydroxy-3-isopropylphenyl) ether, bis(4 hydroxy 3 chlorophenyl)ether, bis(4 hydroxy 3 fiuorophenyDether, bis(4 hydroxy 3 bromophenyl)ether, bis(4 hydroxynaphthyl)ether, bis(4 hydroxy 3-chloronaphthyl)ether, bis(Z-hydroxydiphenyl) ether, 4,4-dihydroxy-2,6-dimethoxy-diphenyl ether, 4,4- dihydroxy-2,5-diethoxydiphenyl ether, and the like;

Also suitable are the bisphenol reaction products of 4- vinylcyclohexene and phenols, e.g. 1,3-bis(p-hydroxyphenyl)-1-ethylcylohexane, and the bisphenol reaction products of dipentene or its isomers and phenols such as 1,2-bis(p-hydroxyphenyl) l-methyl 4-isopropylcyclohexane as well as bisphenols such as 1,3,3-trimethyl-1-(4- hydroxyphenyl)-6-hydroxyindane, and 2,4-bis(4-hydroxyphenyl)-4-methylpentane, and the like.

Particularly desirable dihydric polynuclear phenols have the formula )r (Yr) 2 wherein Y and Y are as previously defined, r and 1 have values from 0 to 4 inclusive and R is a divalent saturated aliphatic hydrocarbon radical, particularly alkylene and alkylidene radicals having from 1 to 3 carbon atoms, and cycloalkylene radicals having up to and including 10 carbon atoms.

Mixtures of dihydric phenols can also be employed and whenever the term dihydric phenol or dihydric poly nuclear phenol is used herein, mixtures of these compounds are intended to be included.

The epoxide contributing the hydroxyl containing radical residuum, E, can be a monoepoxide or diepoxide. By epoxide is meant a compound containing an oxirane group ,i.e., oxygen bonded to two vicinal aliphatic carbon atoms, thus,

A monoepoxide contains one such oxirane group and provides a radical residuum E containing a single hydroxyl group; a diepoxide contains two such oxirane groups and provides a radical residuum E containing two hydroxyl groups. Saturated epoxides, by which term is meant diepoxides free of ethylenic unsaturation i.e. C= and acetylenic unsaturation, i.e. -CEC, are preferred.

Particularly are halogen substituted saturated monoepoxides i.e. the epihalohydrins and saturated diepoxides which contain solely carbon, hydrogen and oxygen, especially those wherein the vicinal or adjacent carbon atoms form a part of an aliphatic hydrocarbon chain. Oxygen in such diepoxides can be, in addition to oxirane oxygen, ether oxygen O-, oxacarbonyl oxygen carbonyl oxygen and the like.

Specific examples of monoepoxides include epichlorohydrins such as epichlorohydrin, epibromohydrin, 1,2- epoxy l-methyl 3-chloropropane, 1,2-epoxy 1-butyl-3- chloropropane, 1,2-epoxy-2-methyl-3-fluoropropane, and the like.

Illustrative diepoxides include diethylene glycol bis (3,4 epoxycyclohexane-carboxylate), bis(3,4 epoxycyclohexylmethyl) adipate, bis 3,4-epoxycyclohexylmethyl) phthalate, 6-methyl-3,4-epoxycylohexylmethyl 6-methyl- 3,4-epoxycylohex-ane carboxylate, 2-chloro-3,4-epoxycyclohexylmethyl 2 chloro 3,4 epoxycylohexanecarboxylate, diglycidyl ether, bis(2,3-epoxycyclopentyl)ether, 1,5- pentanediol bis(6 methyl 3,4 epoxycyclohexylmethyl) ether, bis(2,3-epoxy-2-ethylhexyl)adipate, diglycidyl male ate, diglycidyl phthalate, 3-oxatetracyclo [4.4.0.l .0 undec-S-yl 2,3 epoxypropyl ether, bis(2,3 epoxycyclopentyl)sulfone, bis(3,4-epoxyhexoxypropyl) sulfone, 2,2- sulfonyldiethyl bis(2,3 epoxycyclopentanecarboxylate), 3-oxatetracyclo [4.4.0.1 .0 ]undec-8-yl 2,3 epoxy butyrate, 4 pentenal-di(6 methyl 3,4 epoxycyclohexylmethyl)acetal, ethylene glycol bis(9,10-epoxystearate), diglycidyl carbonate, bis(2,3-epoxybutylphenyl)2-ethylhexylphosphate, diepoxydioxane, butadiene dioxide and 2,3-dimethyl butadiene dioxide. The preferred diepoxides are those wherein each of the oxirane groups is connected to an electron donating substituent which is not immediately connected to the carbon atoms of that oxirane group. Such diepoxides have the grouping wherein A is an electron donating substituent such as Q and Q is a saturated hydrocarbon radical such as an alkyl, cycloalkyl, aryl or aralkyl radical.

A single monoepoxide or diepoxide or a mixture of at least two monoepoxides or diepoxides can be employed in preparing thermoplastic polyhydroxyethers and the terms monoepoxide and diepoxide are intended to include a mixture of at least two monoepoxides or diepoxides, re

spectively.

The thermoplastic polyhydroxyether adhesive compositions of this invention can be prepared by any of the blending or mixing means conventionally used to mix or compound thermoplastics. For example, suitable techniques include codissolving and blending of solutions of the components, working in a Banbury mixer, a compounding extruder, or on a roll mill or in equivalent apparatus. Fluxing the adhesive composition components during a portion of the mixing in these apparatus is preferred to insure homogeneity of the final composition.

The invention is illustrated by the following examples wherein all proportions, parts, and percentages are by weight unless otherwise stated. Melt flow of each of the thermoplastic polyhydroxyethers was determined by weighing in grams of the amount of polyhydroxyether which, at a temperature of 220 C. and under a pressure of 44 p.s.i., flowed through an orifice having a diameter of 0.825 and a length of 0.315 over a ten minute period. Four such determinations were made and the average of the four determinations is reported as decigrams per minute under a pressure of 44 psi. and at 220 C.

Example 1 Grams 2,2-bis(4-hydroxyphenyl)propane (0.5 mole) 114.5 Epichloronydrin (99.1%) pure (0.5 mole) 46.8 Ethanol 96.0 Butanol 10.0 Sodium hydroxide (975%) pure 22.6 Water 70.0

The above mixture was stirred at room temperature for 16 hours to accomplish the initial coupling reaction. The mixture was then heated at 80 C. for one hour. Sixty milliliters of a 7:3 mixture of toluenezbutanol was added to the flask. Heating of the mixture at 80 C. was continued another two hours. There was added to the flask an additional 50 milliliters of the 7:3 toluenezbutanol mixture and 4.5 grams of phenol. The contents of the flask were continued heated at 80 C. (reflux) for 2 /2 hours. Upon cooling, the reaction mixture was cut with 200 milliliters of the 7:3 toluenezbutanol mixture. One hundred milliliters of water was added to the flask and agitated with the contents to dissolve salts present in the reaction mixture. The flask contents were allowed to settle for ten minutes during which time a lower brine phase formed. This lower phase was separated by decantation. The upper polymer solution containing phase was washed successively with two 160 milliliter portions of water containing 4.5 butanol. The washed polymer solution was acidified by stirring the solution with a mixture of l milliliter of 85% phosphoric acid with 100 milliliters of water (pH=2) for one hour. The upper polymer solution phase was again separated by decantation and water washed with four successive 200 milliliter portions of water containing 4.5% butanol. The washed polymer was then coagulated in one liter of isopropanol, filtered, and dried. There was obtained a thermoplastic polyhydroxyether of 2,2 bis(4 hydroxyphenyl)propane and epichlorohydrin having a melt flow of 6.0 decigrams per minute.

Example 2 E xample Pol ychloroprcne 'Ih erm oplastie 1 ap Sh ear Polyhydroxyether Strength Control... 100 2, 000 1 u 95 3, 790 2 1 5 85 4, 210

The following are illustrations of the composition and benefits of the invention.

(3) Employ a chloroprene polymer containing 5, 10, and percent of copolymerized a-methylstyrene, acrylonitrile or butadiene in the rubber. Equivalent results were obtained.

(4) Vary the polychloroprene content in any of the foregoing specific compositions to prepare compositions having 5, 10, 15, 20, 25, 30, 33, 35, and parts of polychloroprene per 100 parts of the polychloroprene and polyhydroxyether taken together. Equivalent results are obtained.

(58) Examples 1 and 2 are each duplicated but sub stituting for the polyhydroxyether a 6 melt flow poly(hydroxyetherdihydroxyether) prepared as in Example 1 but with the substitution of 0.25 mole of butadiene dioxide for 0.25 mole of epichlorohydrin (5 and 6) and with substitution of a 6 melt flow polyhydroxyether prepared as in Example 1 but using 0.5 mole of the diglycidyl ether of 2,2-bis(4-hydroxyphenyl) propane for all the epichlorohydrin (7 and 8). An improvement in peel and shear strengths is noted.

What is claimed is:

1. Laminate of a substrate and a composition which develops high bond strengths at relatively low bonding temperatures which comprises a mixture of from 50 to 97 parts by weight of thermoplastic polyhydroxyether having the general formula wherein D is the radical residuum of a dihydric phenol, E is an hydroxyl containing radical residuum of an epoxide, and n represents the de ree of polymerization and is at least 30 and from 3 to 50 parts by weight of chloroprene polymer selected from the group consisting of homopolymers of chloroprene and copolymers of chlo- :roprene wherein at least of the copolymer consists of chloroprene units per 100 parts by weight of the mixture.

2. Laminate of a substrate and a composition which develops high bond strengths at relatively low bonding temperatures which comprises a mixture of from 67 to parts by Weight of thermoplastic polyhydroxyether having the general formula wherein D is the radical residuum of a dihydric phenol, E is an hydroxyl containing radical residuum of an epoxide, and n represents the degree of polymerization and is at least 30 and from 5 to 33 parts by weight of chloroprene polymer selected from the group consisting of homopolymers of chloroprene and copolymers of chloroprene wherein at least 80% of the copolymer consists of chloropren units per parts by weight of the mixture.

3. Laminate claimed in claim 2 wherein the thermo plastic polyhydroxyether has a melt flow of less than about 7, and the chloroprene polymer is present in an amount of about 5 to 15 parts by weight per 100 parts of the mixture.

4. A structural element exhibiting improved bond strength comprising an 'adherend and adhering thereto an adhesive composition comprising a mixture of from 50 to 97 parts by weight of thermoplastic polyhydroxyether having the general formula -EDO--EOilwherein D is the radical residuum of a dihydric phenol, E is an hydroxyl containing radical residuum of an epoxide, and n represents the degree of polymerization and is at least 30 and from 3 to 50 parts by weight of homopolymer of chloroprene per 100 parts by weight of the mixture.

5. A structural element exhibiting improved bond strength comprising an adherend and adhering thereto an adhesive composition comprising a mixture of from 67 to 95 parts by weight of thermoplastic polyhydroxyether having the general formula {-D-OEO- wherein D is the radical residuum of a dihydric phenol, E is an hydroxyl containing radical residuum of an epoxide, and n represents the degree of polymerization and is at least 30 and from 5 to 33 parts by weight homopolymer of chloroprene per 100 parts by weight of the mixture. I

6. A structural element exhibiting improved bond strength comprising an adherend and adhering thereto an adhesive composition comprising a mixture of from 85 9 to 95 parts by weight of thermoplastic polyhydroxyether and having the general formula wherein D is the radical residuum of a dihydric phenol, E is an hydroxyl containing radical residuum of an epoxide, and n represents the degree of polymerization and is at least 30 and from to parts by weight of homopolymer of chloroprene per 100 parts by weight of the mixture.

7. A structural element having improved bond strength comprising at least one steel adherend and at least one stainless steel adherend said adherends being bonded together with an adhesive composition comprising a mixture of from 67 to 95 parts by weight of thermoplastic polyhydroxyether having the general formula wherein D is the radical residuum of a dihydric phenol, E is an hydroxyl containing radical residuum of an epoxide, and n represents the degree of polymerization and is at least 30 and from 5 to 33 parts by weight of homopolymer of chloroprene per 100 parts by weight of the mixture.

8. Method of achieving high strength bonds between adherends comprising placing between opposing faces of a pair of adherends an adhesive composition comprising a mixture of from 67 to 95 parts by weight of thermoplastic polyhydroxyether having the general formula wherein D is the radical residuum of a dihydric phenol, E is an hydroxyl containing radical residuum of an epoxide, and n represents the degree of polymerization and is at least 30 and from 5 to 33 parts by weight of chloroprene polymer selected from the group consisting of homopolymers of chloroprene and copolymers of chicroprene wherein at least 80% of the copolymer consists of chloroprene units maintaining said faces in contact with the adhesive, subjecting the adherend-adhesive-adherend 4O assembly to a temperature sufficient to cause the adhesive to bond and cooling the assembly.

wherein D is the radical residuum of a dihydric phenol, E is an hydroxyl containing radical residuum of an epoxide, and n represents the degree of polymerization and is at least 30 comprising forming a mixture thereof comprising from 3 to parts of a chloroprene polymer selected from the group consisting of homopolymers of chloroprene and copolymers of chloroprene wherein at least of the copolymer consists of chloroprene units and from 50 to 97 parts of the polyhydroxyether, all parts being by weight.

11. Method of improving low temperature bonding properties of thermoplastic polyhydroxyether having the general formula wherein D is the radical residuum of a dihydric phenol, E is an hydroxyl containing radical residuum of an epoxide, and n represents the degree of polymerization and is at least 30 comprising forming a mixture thereof comprising from 5 to 15 parts of a chloroprene polymer selected from the group consisting of homopolymers of chloroprene and copolymers of chloroprene wherein at least 80% of the copolymer consists of chloroprene units and from to parts of the polyhydroxyether, all parts being by weight.

12. Method claimed in claim 11 wherein the chloroprene polymer is homopolymer of chloroprene.

No references cited.

MURRAY TILLMAN, Primary Examiner.

P. LIEBERMAN, Examiner. 

1. LAMINATE OF A SUBSTRATE AND A COMPOSITION WHICH DEVELOPS HIGH BOND STRENGTHS AT RELATIVELY LOW BONDING TEMPERATURES WHICH COMPRISES A MIXTURE OF FROM 50 TO 97 PARTS BY WEIGHT OF THERMOPLASTIC POLYHYDROXYETHER HAVING THE GENERAL FORMULA 